On large floor surfaces, floorcovering is installed in multiple pieces in order to fully cover the surface. During installation, the edges of the abutting layers of floorcovering are bonded or “seamed” together to form a contiguous layer of floorcovering over the floor surface. This requires that there are minimal or no gaps along the closed seam. Often, the closed seam is formed by overlapping one layer of floorcovering over another and then cutting both layers at once. This produces a closed seam that has virtually no gaps along its length. Typically, resilient flooring is seamed by laying the vertical edges of adjacent and abutting layers in close contact, folding back the adjacent marginal portions of the floorcovering to expose the sub-floor, applying a band of flooring adhesive along the line of abutment using a spreader and then bringing the marginal portions back together onto the sub-floor and rolling the seam with a hand roller to ensure adhesion between the floorcovering and the sub-floor. With certain types of resilient flooring, it is necessary that some adhesive squeeze up along the line of abutment thereby gluing the edges of abutting layers to each other in addition to the sub-floor. This technique is used in the installation of carpet as well.
In the early-nineties, one of the present applicants developed a novel applicator tip for dispensing adhesive to seam adjacent layers of floorcovering. This was disclosed in U.S. Pat. No. 5,520,145 issued Oct. 5, 1993. This applicator tip is hereinafter referred to as the “prior tip”.
The prior tip is used to apply adhesive to the edges of abutting pieces of floorcovering and to the sub-floor underneath the floorcovering along the line of abutment when the floorcovering is glued directly to the sub-floor. The prior tip comprises a fixed opening for connection with an adhesive dispenser such as a squeeze bottle and outlet orifices to dispense adhesive on the edges of the floorcovering and to the sub-floor itself. The prior tip is placed in the open seam and manually advanced by pulling it along the line of abutment from one end of the seam to the other end while the bottle is squeezed. In doing so, adhesive is dispensed on the edges and to the sub-floor along the line of abutment.
This method is usually performed in stages or portions along the line of abutment. Adhesive is first applied to a span of approximately 12″ to 18″ and then the edges of the floorcovering are manually brought into close contact with one another and then hand-rolled to form the finished seam. This process is repeated along the line of abutment until the finished seam is completed. One problem with the prior tip is that the adhesive dispenser attached to the prior tip is oriented upwards at an angle leading in the direction that the prior tip follows to form the finished seam. As the dispenser and prior tip are advanced along the line of abutment towards a wall, the dispenser prevents the tip from being advanced right up tight to the wall. To finish the seam, the prior tip must then be turned around 180 degrees and be advanced backwards from the wall towards the point where it was stopped previously.
In the art of installing floorcovering, it is also known to use a backing tape to reinforce a finished seam. This involves applying the backing tape to the back of the floorcovering along the line of abutment. The backing tape reinforces the finished seam to provide additional resistance against the adjacent layers being pulled apart. The current method of installing a backing tape involves gluing the backing tape to the sub-floor or pad underneath the line of abutment with a floor adhesive. The marginal edge portions of the floorcovering are then glued to the backing tape.
The backing tape itself is comprised of lines or strips of thermoplastic adhesive on its top surface running along its length. To activate the thermoplastic adhesive so that the floorcovering will bond to the backing tape, a heating iron is placed in the open seam between the floorcovering and the backing tape. The iron heats the thermoplastic adhesive until it becomes molten. The iron is then manually drawn along the backing tape to heat a portion of the backing tape adhesive. While the thermoplastic adhesive is still molten, the edges of the abutting floorcovering layers are fitted to one another and then hand-rolled such that the marginal edge portions are brought into contact with the molten adhesive and are bonded to the backing tape as the adhesive cools and sets.
There are a number of disadvantages with this method. First, no adhesive is placed between the abutting edges of the floorcovering. The only bonding that occurs is between the bottom surface of the marginal portions of the floorcovering and the backing tape. Second, there is a risk that the heat produced by the iron to melt the thermoplastic adhesive will melt or burn the floorcovering itself. Third, this method is difficult to used when making finished seams that are curved. The bulkiness of the backing tape with thermoplastic adhesive makes the tape difficult to bend and form curves. Fourth, gluing the backing tape to the sub-floor or pad makes it difficult to move the backing tape once the floor adhesive begins to set to compensate for any adjustments in placement of the floorcovering when the finished seam is formed. Lastly, this method of installation is awkward and requires considerable skill to produce a finished seam.
It is therefore desirable to seam abutting layers of floorcovering with a backing tape without the shortcomings of the prior art method.